Electrode mounting



E. STEUDEL ELECTRODE MOUNTING May 28, 1940.

Filed July 31, 1937 INVENTOR 5. .STEUDEL ATTORN EY fiatenteci May 28, 1946 PATENT OFFICE ELECTRODE MOUNTING Eberhard Steudel, Berlin-Dahlem, Germany, as-

signor to Allegemeine Elektricitatz Gesellschaft,

Berlin, Germany Application July 31, 1937, Serial No. 156,611

In Germany August 21, 1936 3 Claims.

The invention relates to means and method for mounting electrodes in tubes, more especially in the case of cathode ray tubes. The difficulties are known which are encountered when attempting to obtain an electrode mounting that is at the same time rigid and simple, and many suggestions have already been made to solve this problem. The hitherto known methods are generally based upon the following twoprinciples:

Either one electrode is mounted on the other one,

' with insulating pieces accordingly placed between the successive electrodes, or else all electrodes are arranged on a single or several common insulating bodies. In the latter case the fastening of the electrodes to the insulating bodies proper causes difficulties.

In accordance with the invention an entirely new measure is resorted to. The electrodes are mounted on four, or a greater number of throughgoing rods of insulating material in such manner that the electrodes to be mounted are provided for each rod always with two metal strips (shells) so shaped that openings for the rods are obtained therein, that each shell is placed half around the 5 rod for the mounting, and that the shells situated opposite each other are joined together. This connecting together may be carried out for instance through spot welding.

The invention may best be explained by reference to the drawing wherein:

Fig. 1 shows, by way of example, a complete view of the improved electrode mounting means,

' glass fitting on the mounting rods. Items 4 and 5 indicate the plate pairs. The system'serving for the concentration of the electron ray is represented by the parts 6 to II, whereby 6 is the anode diaphragm, I the anode cylinder, 8 an in- 5 sulating ring preferably formed of ceramic material, is an intermediate cylinder, III a second insulation ring, and II is a cap supporting the Wehnelt cylinder. Items I2 and I3 are two disks of insulating material preferably mica, the

M center of which having guide openings 22 and Characters 3 represent 23 (see Figure 6) serving for supporting the cathode. The guide cylinder of the cathode is designated by I l and item I5 represents the press or the cathode lead-ins. The closure of the tube is shown herein in the form of the known acorn- 5 type tube in which the glass neck and the tubular glass attachment are providedwith a flange I6 between which the lead-in wires of the tube are squeezed in.

The ray concentration system is again shown 10 in Figure 2 displaced by 90. The supporting rods are omitted rendering clearly visible the shells serving for the mounting. According to a further idea of the invention the electrodes to be mounted which have rotation symmetry are pro- 15 duced of two parts, preferably identical, each part being provided with two shells for mounting on two oppositely situated rods, as shown in Figure 3 which represents the cross section of such an electrode (for instance of the intermediate cylin- 2o der 9) at right angle to the axis of the ray. Each of these parts may be stamped out of sheet metal. The electrodes which are not so mounted, for instance the anode diaphragm I5, need not be formed of two pieces. 20

Figure 4 shows again the electrode system in this case a cross section along the axis. The figure shows that the intermediate cylinder 9 may be provided with a light stop I'I. Also, supported by the cap II is the Wehnelt cylinder Iii into so which projects in part the cathode I9 which is inserted through the mica disk I2. The anode I is formed as a cap closed up by the light stop 6 and placed on the intermediate cylinder 9 by means of the properly fitting insulation ring 8. In like manner the cap I I is maintained in proper position by the ring ID.

The upper and lower closure of the system are represented in the Figures 5 and 6.

Each of the insulating rods has fused into the 40 upper end a wire 28 (Figure 5). Thereafter metal caps I are placed over the rods, these caps ending into small tubings through which the wires 28 are passed. The fastening of the wires to the caps is carried out, for instance, by spot fusing while the caps are pushed downwards so that. through a certain tension the stability of the shells placed over the rods is thereby increased. The ring 2 may yet be provided with small springs in serving for the secure mounting of the ring and hence of the system in the glass tube.

Similarly, the lower closure of the system (Figure 6) is provided. In this case it suflices to bend the fused-in wires whereby the lower plate I3 is held in place. The wires 2| may eventually serve at the same time as lead-in wires for the potential to be applied to the electrodes. However, also other lead-ins not indicated in the drawing, may be provided. Furthermore, appropriate lead-ins for the deflecting plates may also be provided. Preferably the plates l2 and I3, or at least one of them, are so designed that they can serve as spacer for the system in the tube.

The deviation plates are preferably stamped out as a unit and mounted by means of shells on two neighboring rods. are preferably so mounted that each electrode is held on two opposite rods, while the fastening is carried out alternately at the one and at the other pair of opposite rods. In order to increase the stability the spacers 3 are arranged throughout between the mounts of the rods to be mounted, 1. e., also at the places not indicated in the Figure 1 for the sake of clearness.

Various modifications may be made in my invention Without departing from the spirit or scope thereof and it is desired that no limitations be placed thereon other than those imposed by the prior art or by the claims herein included.

I claim as my invention:

1. A cathode ray tube comprising an envelope, a plurality of insulating mounting rods, means for maintaining the rods fixed with respect to each other and with respect to the envelope, a plurality of electrodes, means for frictionally securing the electrodes to the mounting rods, spacer means positioned between at least two of the electrodes to maintain the electrodes in proper longitudinal position on the rods, and means fused The other electrodes on at least one end of each of the mounting rods for maintaining the elements in rigid assembled relation.

2. A cathode ray tube comprising an envelope, a plurality of fusible insulating mounting rods, means for maintaining the rods fixed with respect to each other and with respect to the envelope, a plurality of electrodes, means for frictionally securing the electrodes to the mounting rods, spacer means positioned between the electrodes, means on at least one end of each of the mounting rods for maintaining the elements in rigid assembled relation, said last named means comprising a wire fused into one end of the mounting rods, a metal cap and means at one end of said cap for engagement with said wire.

3. A cathode ray tube comprising an envelope, a plurality of fusible insulating mounting rods, means for maintaintaining the rods fixed with respect to each other and with respect to the envelope, a plurality of electrodes, means for frictionally securing the electrodes to the mounting rods, tubular spacer means positioned between each electrode securing means, and means at each end of each said mounting rod for maintaining the elements in rigid assembled relationship, said last named means comprising a wire fused into one end of said mounting rods, a metal cap member adapted to be placed over the end of each of the said mounting rods, and means at the end of said cap for fusible engagement with said wire.

EBERHARD S'I'EUDEL. 

